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#include <windowClass.h>
void Window::setupRender(){
glClearColor(0,0,0,0); //set the background color
}
void Window::render(){
//a matrix is a blank canvas for the computer to draw on, the matrices are stored in a "stack"
//GL_PROJECTION has 2 matrices
//GL_MODELVIEW has 32 matrices
glMatrixMode(GL_PROJECTION); //set the matrix mode as projection so we can set the ortho size and the camera settings later on
glPushMatrix(); //push the matrix to the top of the matrix stack
glLoadIdentity(); //replace the entire matrix stack with the updated GL_PROJECTION mode
glOrtho(0,SCREEN_WIDTH, 0,SCREEN_HEIGHT, -1,1); //set the the size of the screen
glMatrixMode(GL_MODELVIEW); //set the matrix to modelview so we can draw objects
glPushMatrix(); //push the matrix to the top of the matrix stack
glLoadIdentity(); //replace the entire matrix stack with the updated GL_MODELVIEW mode
glPushMatrix(); //basically here we put a blank canvas (new matrix) on the screen to draw on
glClear(GL_COLOR_BUFFER_BIT); //clear the matrix on the top of the stack
/**************************
**** RENDER STUFF HERE ****
**************************/
glColor3f(1.0f, 0.0f, 0.0f); //color to red
glRectf(0,0, 50,50); //draw a test rectangle
glColor3f(0.0f, 1.0f, 0.0f); //color to blue
glRectf(50,0, 100,50); //draw a test rectangle
glColor3f(0.0f, 0.0f, 1.0f); //color to green
glRectf(100,0,150,50); //draw a test rectangle
/**************************
**** CLOSE THE LOOP ****
**************************/
glPopMatrix(); //take the matrix(s) off the stack to pass them to the renderer
SDL_GL_SwapWindow(window); //give the stack to SDL to render it
}
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